Objective To investigate the cellular phenotype involved in experimental autoimmune uveoretinitis (EAU) and apoptosis of infiltrating cells in this inflammation． Methods Immunohistochemical staining and in situ apoptosis staining were performed using monoclonal antibodies to monocytes and macrophages (EDI),MHC calss -II antigen (OX6),T lymphocytes (R73) and TACS 1 Klenow kit on both ocular sections and wholemounts of 16 Lewis rats after immunization with interphotoreceptor retinod-binding protein(IRBP). Results EAU was induced in 12 of 16 Lewis rats with a clinical inflammation score being 1.29plusmn;0 .7.Influx of monocytes,lymphocytes and MHC class II+ cells into the uvea and retina was noted after immunization with IRBP.Apoptosis of infiltrating cells was observed in the uvea and retina and more apoptotic cells were present in the iris and ciliary body compared with the choroid and retina. Conclusion A number of cells including monocytes,macrophages,lymphocytes and MHC class II+ cells are involved in EAU induced by IRBP.Apoptosis of infiltrating cells occurs at early stage of EAU,which may greatly contribute to the rapid regression of the inflammation induced by IRBP. (Chin J Ocul Fundus Dis，2000，16：1-70)
Objective To investigate the effect on proliferation and apoptosis of vascular endothelial cells exposed to high glucose. Methods The cultured human umbilical vein endothelial cells (HUVEC) were treated with high glucose at concentrations of 10,20,30,40,50 mmol/L for 2,4,6,8,10,12,14 days,cpm value was studied by using tritium-labelled thymidine deoxyribose(3H-TdR)incorporation assay.Flow cytometry was used to detect apoptosis index,proliferation index and cell cycle. Results Treated with high glucose,the proliferation index and cpm were significantly reduced in a dose and time dependent manner than the control groups(Plt;0.05).The apoptosis index of HUVEC were higher compared with the control groups(Plt;0.05).The percent of the cultured cells in G1 phase in all high glucose groups were increased,the percent in S phase were largely decreased(Plt;0.05). Conclusion Exposed to high glucose,the apoptosis of HUVEC was accelerated and the suppressive effect of high glucose on the proliferation of HUVEC was observed.Endothelial cells were possibly arrested in G1/S checkpoint. (Chin J Ocul Fundus Dis,2000,16:177-180)
Objective To study hyperthermia induced apoptosis and the effect of aspirin on hyperthermia induced apoptosis in retinoblastoma cells. Methods Retinoblastoma cells (Y79) were divided into two groups:hyperthermia groups,hyperthermia+aspirin (0.18～18mu;g/ml) groups.Heat shock condition:44℃,heat shock time:10,20,30, and 40 minutes respectively.The following events were studied after heat shock by using FAC Scan: ①cell apoptosis; ②heat shock protein 70 (HSP70) expression；③bcl-2 expression. Results Apoptosis was induced by the treatment of hyperthermia (44℃) in Y79 cells in a heat dose dependent fashion.Longer time heating (44℃，40 minutes) induced necrosis rather than apoptosis.Aspirin could rescue Y79 cells from hyperthermia induced apoptosis in a dose dependent manner．HSP70 was induced in Y79 cells after heat shock,it was further enhanced by the treatment of aspirin(＞1.8mu;g/ml).Heat shock itself showed no effect on bcl-2 expression in Y79 cells,aspirin,on the other hand,could enhance bcl-2 expression in a modest level in heat treated Y79 cells. Conclusions Hyperthermia may induce apoptosis in Y79 cells which can be protected by use of aspirin．The enhancement of HSP70 and bcl-2 expression in Y79 cells by the treatment of aspirin in heating condition may be responsible for the protective function. (Chin J Ocul Fundus Dis, 1999, 15: 143-145)
Objective To examine the influence of retinal pigment epithelium(RPE) cells on antigen-specific activatedlymphocytes in vitro,and to explore the role of RPE cells in the immune privilege of the eye. Methods Co-culture systems of RPE cells with antigen-specific T lymphocyte lines and resting T lymphocytes were established in vitro．Induction of apoptosis was detected by genomic DNA electrophoresis,DNA in situ end-labelling and flow cytometry. Results RPE cells induced apoptosis in antigen-specific activated T lymphocytes. 24 hours after culture,the signs of apoptosis appeared in lymphocytes co-incubated with RPE cells．As time of co-culture went on,the number of apoptosic cells increased．Quantitative analysis of apoptosic cells showed that apoptosic cells accounted for 5.95% after 24 hours, 9.38% after 48 hours,and 17.95% after 72 hours．In contrast,RPE cells induced few apoptosis in resting T lymphocytes. Conclusions These results suggest that RPE cells possess the ability to induce the apoptosis of invading lymphocytes. This phenomenon serves as a restrain mechanism of immune response and may be of vital importance in the maintenance of immune privilege in posterior segment of eye and in the protection of eye from the damage of immunogenic inflammation. (Chin J Ocul Fundus Dis, 1999, 15: 241-244)
PURPOSES:To investigate the time of neuronie apoptosis in the retinas of Imman fetuses,and its relations with neuronie proliferation and differentiation, METHODS:The retinas of 27 human fetuses from 8th to 38th week of R,~til- ization age and 3 adults were studied by TdT-mediated dUTP nick end labelling(TUNEL) method. RESULTS:Tbe nuctei of labeled apoptotic cells were charaeterised by nuclear marginization,ehromatln condensation and cleseent shape,and some apoptotie bodies were visible in the specimens. The apoptosis of neuroepithelium of fetal rclina took place during 8th to 18th week, Apoptosis of ganglion cells were observed from 1256 to 18th week. The apoptos[s of pholorec, plors were formd from 14th to 2Ist week ,while thai of bipolar neurones and M~ller cells were found from ldth to 28th week. No apoptosb of ocstones were observed in the retinas after 28th week of fertilization age and within the retinas of adults. CONCLUSION:The proliferating cells of neuroepithelium and Ihe neurones which just differetiated from fetal retina might partly undergo apoptosis. The time of apoptosls of differentiated neurones was consistent with the time of the synapses formation between neurones and their targel cells. （Chin J Ocul Fundus Dis,1997,13:67 -69 ）
OBJECTIVE:To investigate the cytotoxic effects of homoharringtonine(HHT) on HXO-RB44 cell line and the cell death form induced byHHT in vitro. METHODS:MTT assay was adopted to establish survival rate of the tumor cells. Agarose gel electrophores was chosen to detect the genomic DNA from the cells exposed to HHT. RESULTS:In the concentration from 10-9 to10-4 mol/L HHT powerfully inhibited the growth of the cells (P＜0.05). Regular genomic DNA fragmentation from the cells exposed to 10-6mol/L HHT for 48 hours was shown to be typical DNA ladder on agarose gelelectrophoresis. CONCLUSION :HHT can induce retinoblastoma (RB) programmed cell death (PCD),the effects of which has close correlation with incubated period and concentration of HHT.
【摘要】 目的 探讨铁螯合剂去铁胺（DFO）对诱导白血病细胞HL-60的分子机制。 方法 2003年7-12月用钙黄绿素（calcein）检测HL-60细胞LIP。台盼蓝活细胞拒染实验进行活细胞计数及细胞存活率测定；光镜形态学观察及流式细胞仪（FCM）等方法检测HL-60细胞凋亡；比色法检测caspase-3（基于pNA标记底物的比色法）活性。 结果 ①不同浓度的DFO作用于HL-60细胞后，随培养时间延长及DFO浓度的增加，动态铁池降低，细胞生存率逐渐下降，凋亡率增加，显示一定的时间剂量依赖性。②HL-60细胞在不同浓度的DFO作用下，caspase-3的活性逐渐升高。50、100 μmol/L DFO作用于HL-60细胞24 h，caspase-3酶活性升高明显，与对照组相比，有统计学意义（Plt;0.001）；相关分析结果显示，HL-60细胞LIP的改变与caspase-3活性变化呈负相关系（r=-0.887，Plt;0.05）。 结论 DFO诱导白血病细胞凋亡的作用可能与螯合细胞内铁，降低细胞LIP，激活caspase-3，最终实施细胞凋亡密切相关。【Abstract】 Objective To observe the changes of caspase-3 activity during apoptosis of HL-60 cells induced by an iron deferoxamine (DFO). Methods Exponentially growing HL-60 cells (1×106/mL) were used in this experiment from July 2003 to December 2003. The study groups were divided as follows: DFO group, iron+DFO group and control group. The viability was detected by typanblue, apoptosis was assessed by morphological study and flow cytometry (FCM) assay, and the caspase-3 activity was detected by melorimetry. The intracellular label iron pool (LIP) was measured with a fluorimetric assay using the metalsensitive probe calcein-AM. Results ①When HL-60 cells were incubated with different concentrations of DFO, viability assay was lower than that in the control group at the 12th, 24th and 48th hour (Plt;0.05). ② The cells incubated with different concentrations of DFO showed dose-time dependence and was much higher than that in the control group (Plt;0.01). ③The caspase-3 activity was significantly higher in the apoptotic cells than that in the control cells. Conclusions The apoptosis of HL-60 cells induced by DFO may be correlated with the decrease of cellular LIP and activity of caspase-3.